Ingot-mold set-up



Patented June 12, 1928.

UNITED STATES PATENT OFFICE.

WILLIAM HAIG RAMAGE, OF GIRARD, OHIO, ASSIGNOR TO VALLEY MOULD &. IRONCORPORATION, OF HUBBARD, OHIO, A CORPORATION OF NEW YORK.

INGOT-MOLD SET-UP.

Application filed July 28, 1926. Serial No. 125,370.

This invention relates broadly to metallurgy and more particularly toingot molds and the like.

Heretoforc in the art, ingot molds have been formed with matrices havingrounded closed bottoms. The curvature of the bottom walls of such moldswas to avoid dendritic crystallization in ingots cast in such molds. Thebottom of such an ingot mold is subjected to the most severe cuttingaction due to being struck directly by the stream of molten steel whenthe ingot is being cast.

The result is that the curved bottom portion of the matrix of such moldsquickly becomes cut away. The ingot then sticks in the mold and whenstripped often tears out a portion of the mold wall or else the ingotsticks and cannot be stripped from the mold. In either event, the moldis ruined; The life of such closed bottom molds. is short, as comparedwith straight sided molds used in connection withcasting stools.Furthermore, in the prior art type of rounded closed bottom ingot molds,it was necessary to leave openings in the .bottoms of the molds in orderthat the ingots might be stripped from the molds by introducing astripping member through the openings. It was the usual practice toclose such openings by means of bricks or plugs. Particles of thesebricks frequently stuck to the ingots and when such ingots werereheated, the portions of the bricks would melt and spoil that part ofthe steel where the melted brick particles stuck. Short lived molds addgreatly to the ultimate cost of the steel products fabricated fromingots cast in such molds. In using short lived molds, the fulladvantages, economy, etc., to be gained from the use of rounded bottombig-end-up type molds are lost.

The present invention overcomes the difficulties of the known prior artby providing a mold body having a straight sided matrix of thebig-end-up type in combination with a stool having a deep recess thereinof such conformation as to form a properly rounded end on a steel ingotto obviate dendritic crystallization and to obtain all of the advantagesheretofore obtained in the one piece rounded bottom mold, withoutencountering the disadvantages of such mold.

In the present invention, the mold body and stool are in eflect a twopiece mold; the

body and the curved end being in the stool.

Furthermore, in accordance with the present invention, the matrixsurfaces of the recess in the stool may be chilled and thereby avoidrapid cutting away of this matrix surface. If any cutting does occur, itoccurs in the stool, the mass of which is small compared to the ingotmold body proper. Therefore, the combination comprising the presentinvention is such that the mold body has a relatively long life and theshorter lived stool portion may be replaced from time to time whennecessary without replacing the entire set-up. Furthermore, with thepresent invention, since the mold and stool are separable, a'strippingopening in the bottom of the stool is unnecessary, and the entire'end ofthe ingot is uniformly chilled and the disadvantages incident to the useof a brick in the bottom of the setup is avoided. Preferably, the bottomof the mold and the top of the stool are so finished as to provide ametal to metal joint thereby avoiding any fins on the ingot tofacilitate quickly freezing the metal at the juncture of the mold andthe stool, thus preventing cutting away of the lower inner corner of theingot mold.

It is realized that the present invention may be embodied inconstructions other than that herewith disclosed andtherefore it isdesired that the disclosure herewith shall be considered as illustrativeand not in the limiting sense.

6 is of unusual depth and is provided with a matrix recess 7 comprisinga continuation of the matrix 2 of the mold body of the setup.Preferably, though not necessarily, the metal 8 adjacent the surface ofthe matrix in the stool is chilled metal having a close smooth grainedsurface.- The ends 9 and 10 of the mold body are finished surfaces inorder to cooperate with thetop surface 11 of the or shoulder 12 providesre-entering angularly disposed cold'metal surfaces causing the metaladjacent the metal to metal joint to very quickly freeze and therebyobviate burning out the corner of the mold.

Preferably, the surfaces at 14 in the recess 7 are substantially atright angles to the top surface 11 of the stool and are substantiallyparallel to the side walls of the matrix 2. The bottom of the recess 7is a cupped zone 15 which quickly fills with molten steel and protectsthe stool for the impact of the stream of molten steel.

While the construction illustrated in the drawing shows the matrix ofthe mold arranged as a big-end-up set-up,'it is to be un derstood thatthe present invention is also applicable to set-ups wherein theconstruction comprises a matrix of the big-end-down type and such aset-up merely requires the reversal of the body section on a suitablestool.

In the present invention dendritic crystallization of the steel ingot isavoided by shaping the end of the ingot into curved surfaces by forminga curved surfaced recess in the bottom of the deep stool. The depth ofthe recess will depend largely on the width of the matrix at the bottomofthe body section. Preferably, the depth of the recess shall bebetween25% and 37 of the largest dimension of the cross section of the matrixat the bottom of the mold body. The heavy body of metal in the stoolquickly absorbs heat from the molten steel, thereby obviating cuttingaway of the stool and also forming a good end on the ingot by freezingthe molten steel before any substantial segregation takes place and alsoby 2. An ingot mold set-up comprising a,

body section having a matrix with substantiallystraight side walls, incombination with a stool section forming a metal to metal unluted jointwith the body portion and being provided with a recess forming a part ofthe matrix of the set-up and with the depth of said recess being fromtwenty-five to thirty-seven and one-half percent of the largest diameterof the bottom of the matrix in the body section.

3. An ingot mold set-up comprising in combination a body section havinga substantially plane surfaced finished end, a deep stool having asubstantiall plane surfaced finished top adapted to orm an unluted metalto metal joint with said body section, a deep recess in said stoolcomprising a continuation of the matrix of said body section, saidrecess having a cupped zone in the'bottom thereof with the upperportions of the walls of said recess being atv substantially rightangles to thetop surface of the stool and curving downwardly andinwardly toward said cupped zone.

4. An mgot mold set-up comprising a body mold section in combinationwith an end mold section, said end of the mold section having a .cuppedrecess adapted to'round the end of an ingot-cast in the set-up, saidrecess comprising curved surfaces forming.

continuations of the matrix surfaces of the body section, said bodysection and said end section meeting in an unluted metal to metal jointextending to the matrix of the set-up, and a continuous narrow shoulderon the end section surrounding the mouth of the recess adjacent to saidjoint.

WILLIAM HAIG RAMAGE.

